Simple motorized brewing unit

ABSTRACT

A motorized beverage machine (1) has: —activation means that comprise a motor (3); and —a brewing unit (2) that comprises a first assembly (13) and a second assembly (14) cooperating together, each assembly delimiting part of a brewing chamber (29) for containing an ingredient capsule (30). At least one of these assemblies (14) is: —movable away from the cooperating assembly (13) into an open position within the machine for forming between the assemblies a passage (31) for inserting into and/or removing from the brewing unit the ingredient capsule; and —movable to the cooperating assembly into a closed position for forming the brewing chamber. The motor is a low power motor configured to: —generate a maximum torque of no more than 50 mNm; and/or —consume a maximum power of no more than 50 W, for driving the movable assembly between the open and closed positions.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a National Stage of International ApplicationNo. PCT/EP2011/057235, filed on May 5, 2011, which claims priority toEuropean Patent Application No. 10174412.6, filed Aug. 27, 2010, theentire contents of which are being incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to a beverage machine for the preparationof a beverage from an ingredient capsule. More particularly, the machinehas a brewing unit with a simple motorization for closing the brewingunit in a convenient and safe manner.

For the purpose of the present description, a “beverage” is meant toinclude any human-consumable liquid substance, such as tea, coffee, hotor cold chocolate, milk, soup, baby food, etc. . . . A “capsule” ismeant to include any pre-portioned beverage ingredient, such as aflavouring ingredient, within an enclosing packaging of any material, inparticular an airtight packaging, e.g. plastic, aluminium, recyclableand/or biodegradable packagings, and of any shape and structure,including soft pods or rigid cartridges containing the ingredient.

TECHNICAL BACKGROUND

Certain beverage preparation machines use capsules containingingredients to be extracted or to be dissolved and/or ingredients thatare stored and dosed automatically in the machine or else are added atthe time of preparation of the drink. Some beverage machines possessfilling means that include a pump for liquid, usually water, which pumpsthe liquid from a source of water that is cold or indeed heated throughheating means, e.g. a thermoblock or the like.

Especially in the field of coffee preparation, machines have been widelydeveloped in which a capsule containing beverage ingredients is insertedin a brewing device. The brewing device is tightly closed about thecapsule, water is injected at the first face of the capsule, thebeverage is produced in the closed volume of the capsule and a brewedbeverage can be drained from a second face of the capsule and collectedinto a receptacle such as a cup or glass.

Brewing devices have been developed to facilitate insertion of a “fresh”capsule and removal of the capsule upon use.

WO 2005/004683 and WO 2007/135136 relate to such brewing devices. Thedevices comprise a frame, a fixed holding part for the capsule, amovable holding part which is mounted relative to the frame in a slidingrelationship, one or two knuckle joint mechanisms that provide amechanical system which enables to close in a steady and fluid-tightmanner the holding parts about the capsule while also resisting to thecounter-force acting while re-opening and generated by the internalbrewing pressure, and a handle for directly levering the knuckle jointmechanism. Such a device forms a simple assembly enabling insertion ofthe capsule by vertical fall through a passage in the frame and removalof the used capsule in the same direction as the insertion direction.The handle may serve to cover and uncover the passage for the capsule.The movable parts of the brewing device are actuated manually via thehandle. The manual force required to move the movable parts variesduring closure and opening of the machine and depends on the dimensionaltolerances of the capsules used and the positioning and nature of thecapsules as well as the temperature of the brewing unit.

WO 2009/043630 discloses a beverage preparation machine including abrewing unit having a front part with a passage for inserting a capsuleinto the brewing unit. The front part is arranged to telescope out ofthe machine's housing for uncovering the passage for inserting a capsuleinto the brewing unit and telescopes into the brewing unit for slidingthe passage under the housing and thus covering the passage by thehousing.

From a different approach, the actuation of the movable part of thebrewing device may be motorized. EP 1 767 129 relates to a motor-drivenextraction module for a capsule-based beverage production device. Inthis case, the user does not have to provide any manual effort to openor close the brewing device. The brewing device has a capsule insertionpassage provided with a safety door assembled to the movable part of thebrewing device via a switch for detecting an undesired presence of afinger in the passage during closure and prevent squeezing-injuries bystopping the motor before any finger is caught in the brewing device.

SUMMARY OF THE INVENTION

An object of the invention is to provide a motorized closure function ofthe brewing unit for providing more convenience in loading and ejectionof the ingredient capsule and reducing user's intervention. Anotherobject is to provide a safe operation by reducing the risk of injurieswhile using a motorized beverage machine. Another object is to provideadded value functionalities such as semi-automatic or automatic brewing,rinsing and/or de-scaling modes. Another object is to control optimalconditions for rinsing and/or de-scaling the machine. A further objectof the present invention is to provide a simple motorized closurefunction of the brewing unit.

One or more of these objects are meet by a motorized brewing machineaccording to the independent claim(s). The dependent claims furtherprovide solutions to these objects and/or additional benefits.

The invention relates to a motorized machine for preparing anddispensing a beverage and more particularly to a beverage machine havinga motorized brewing unit. For instance, the machine is a coffee, tea,chocolate, cacao, milk or soup preparation machine. In particular, themachine is arranged for preparing within a beverage processing module abeverage by passing hot or cold water or another liquid through acapsule containing an ingredient, such as a flavouring ingredient, ofthe beverage to be prepared, such as ground coffee or tea or chocolateor cacao or milk powder.

Such beverage preparation typically includes the mixing of a pluralityof beverage ingredients, e.g. water and milk powder, and/or the infusionof a beverage ingredient, such as an infusion of ground coffee or teawith water. For instance, a predetermined amount of beverage is formedand dispensed on user-request, which corresponds to a serving. Thevolume of such a serving may be in the range of 25 to 200 ml, e.g. thevolume for filling a cup or mug, depending on the type of beverage.Formed and dispensed beverages may be selected from ristrettos,espressos, lungos, cappuccinos, café latte, americano coffees, teas,etc. . . . In particular, a coffee machine may be configured fordispensing espressos, e.g. an adjustable volume of 20 to 60 ml perserving, and/or for dispensing lungos, e.g. a volume in the range of 70to 150 ml per serving.

In particular, the motorized beverage machine has:

-   -   activation means that comprise a motor; and    -   a brewing unit that comprises a first assembly and a second        assembly cooperating together, each assembly delimiting part of        a brewing chamber for containing an ingredient capsule.

At least one of these assemblies is:

-   -   movable away from the cooperating assembly into an open position        within the machine for forming between the assemblies a passage        for inserting into and/or removing from the brewing unit the        ingredient capsule; and    -   movable to (e.g. towards) the cooperating assembly into a closed        position for forming the brewing chamber.

The assemblies are relatively movable to one another. One assembly maybe fixed in the machine, e.g. in the main frame or outer housing of themachine, and the other assembly may be movable thereto. Alternatively,both assemblies may be movable in the machine, e.g. in the main frame orouter housing of the machine.

In accordance with the invention, for driving the movable assemblybetween said open and closed positions, the motor is a low power motorconfigured to:

-   -   generate a maximum torque of no more than 50 mNm; and/or    -   consume a maximum power of no more than 50 W.

By providing a low power motor, it is possible to simplify theconstruction and control of the motorized machine. As compared to highpower motors, a low power motor has a smaller inertia due to the reducedmechanical inertia and lower power load. Hence, temporary variations ofthe force (or torque) required from the motor, e.g. to overcome anobstacle or additional friction, is not or less absorbed by thedampening effect of the mechanical inertia and electric load of themotor but timely translated in a temporary increase of required electricpowering of the motor. Moreover, since the motor has a lower mechanicaland electric inertia, interrupting the powering of the motor is notfollowed by a significant discharge of the energy load (mechanical andelectric) of the motor into the mechanical system. It follows that byusing a low power motor, the actual mechanical behaviour of therelatively movable assemblies can be monitored via the power consumptionof the motor. Moreover, the machine does not require end positionsensors to stop the motor when it is about to reach the end positions.The reaching of an obstacle at the end position can be nearlyinstantaneously identified by monitoring the power consumption of themotor the powering of which can be stopped without the risk of the motorforcing the assemblies detrimentally beyond the end position bydischarging its mechanical and electric inertia.

For instance, the motor is arranged to generate a maximum torque of atleast 20 mNm, in particular a maximum torque in the range of 25 to 40mNm.

The motor can be arranged to consume a maximum power in the range of 7to 25 W, in particular 10 to 15 W.

The motor can have an angular speed of up to 10K RPM, such as from 0 to5000 RPM.

The activation means typically includes a transmission means fortransmitting a drive action from the motor to the movable assembly, e.g.one or more transmission gears and/or belts and/or cardans. Forinstance, the transmission means comprises a gear assembly, optionallyhaving a gear ratio of at least 1:100, in particular from 1:200 to 1:500such as 1:250 to 1:450, e.g. 1:300. Typically, the transmission meanshas a force transmission ratio from the motor to the assembly of atleast 1:50, in particular from 1:100 to 1:300 or 1:500.

Hence, the low power of the motor can be compensated by a correspondingtransmission rate to reduce the output speed of the motor and increasethe generated force (or torque).

In one embodiment, the transmission means comprises a worm drive.

More generally, the transmission means is advantageously unidirectional,e.g. by including a worm drive. Hence, when the motor is stopped, themotor cannot be forced by motion of the assemblies since thetransmission means, e.g. via a worm drive, is configured to transmitpower only into one direction, namely from the motor to the assembliesand not vice versa. It follows that no further break or stop system isneeded to maintain the assemblies in a position into which they aredriven by the motor.

Typically, the activation means further comprises:

-   -   water supply means for supplying heated water to the brewing        chamber, e.g. a water source with a pump and/or a heater and a        control unit such as a PCB with a controller and optional memory        device and/or other electronic components (i.e. a PCBA “Printed        Circuit Board Assembly”); and    -   control means for controlling the drive action of the motor,        e.g. a control unit such as a PCB with a controller or a PCBA,        the control means being typically free of end position sensors        in the open position and/or closed position as discussed above.

The control means may include:

-   -   means for measuring at least one electrical parameter        representative of a consumption of power by the motor;    -   means for comparing to a set reference an evolution of this        measured parameter as a function of time during the transfer of        the assembly from the open to the closed position;    -   means for providing to at least one of this activation means an        input resulting from the comparison of the evolution of the        measured parameter to the set reference; and optionally    -   means for providing an input to at least one of the activation        means as a result of the compared evolution of said measured        parameter.

Hence, the circumstances under which the assemblies are moved to theopen and/or closed position can be monitored by monitoring the powerconsumption of the motor. In particular, the required mechanical outputenergy of the motor to produce a movement is directly linked to itsconsumed input energy, e.g. electric energy, can be measured.

The set reference may be based on a power consumption modelisationand/or an empiric power consumption measure under predeterminedconditions, e.g. with or without ingredient capsule in the brewing unit,specific environment of use, etc. . . . The set reference typicallyincludes a tolerance margin to take into account variations that mayoccur e.g. due to the environment of use and/or manufacturing tolerancesand/or handling tolerances.

For example, the motor is controlled to produce an output movement, e.g.rotation of a rotor, at a predetermined speed and/or to operate at apredetermined input voltage for example at constant voltage. To maintainthe predetermined speed and/or voltage, the input powering of the motormay be adjusted in line with the needed output powering, e.g. angularspeed and torque (depending on the constraints under which the motor hasto operate in a given circumstance). In particular, the power supply ofthe motor may be arranged to control the motor's input voltage and themotor can be arranged to draw the required amount of current needed tomaintain the input voltage. By measuring the required motor inputpowering to maintain the desired motor output speed and/or the inputvoltage, the mechanical constraints exercised against the motor outputcan be determined. Such constraints may correspond to normal operationof the motorized machine, e.g. opening or closing the brewing unitassemblies with or without a capsule ingredient, or to an abnormaloperation, e.g. an interference with an obstacle preventing normalopening or closing, such as a human body part e.g. a finger, caughtinbetween the assemblies or inhibiting reopening of the assemblies, e.g.jamming of the brewing unit. In the former case (normal operation), themotorized beverage machine may be configured to allow a correspondingoperation, e.g. beverage preparation or cleaning, or to carry it outautomatically. In the latter case (abnormal operation), a safety modemay be provided, e.g. to stop closure or reopen the assemblies when anundesired obstacle is caught between the assemblies, or stop the motorwhen the brewing unit is jammed e.g. to prevent undesired stress in themachine and allow for example manual unjamming by a user and/or serviceperson, as appropriate.

A safety input can be provided to the motor when detecting a variationof the measured parameter relative to the set reference which isabnormal. Typically, the variation is deemed abnormal when the measuredparameter:

-   -   exceeds a level that is at least 20% above the set reference, in        particular 30 or 40% thereabove such as 50% thereabove; and/or    -   corresponds to a resistance against closure caused by the        presence of an obstacle, in particular a human body part such as        a finger, inbetween the assemblies moving towards the closed        position and prior to reaching thereof, for example a resistance        between the assemblies of the brewing unit in the range from 50        to 200 N, in particular from 75, 100 or 120 to 130 or 150 N.

Providing a reference set that includes a tolerance range, e.g. 20, 30,40 or even 50% relative to a median or average reference set may beappropriate to take into account normal variations of mechanical effectsoccurring in the machine, such as variations of a friction coefficient,temperature and humidity as well as manufacturing tolerances.

The safety input may involve the inversion of the motor action to movethe movable assembly into the open position or reducing or stopping thedrive action of the motor.

The control means may be configured to detect the abnormal variation incomparison to a referential curve representing the normal evolution ofthe electrical parameter as a function of time corresponding to:

-   -   a mode in which the movable assembly is moved into a closed        position with an ingredient capsule inserted in the brewing        chamber (hereinafter the “Capsule closure mode”); and/or    -   a mode in which the movable assembly is moved into a closed        position with no capsule inserted in the brewing chamber        (hereinafter the “Empty closure mode”),

A water supply mode consisting of supplying heated water to the brewingchamber may be initiated when no abnormal variation of the measuredparameter relative to the set reference has been detected and theassembly is in a closed position (“Capsule closure mode or empty closuremode”). The supplying of heated water may involve the circulation, e.g.by using a pump, of water from a source, e.g. a water tank, and/or theheating of water, e.g. continuous or batch heating, to the brewingchamber. The supply of heated water may be controlled, e.g. via one ormore temperature sensors, pressure sensors and/or flowmeters, to adjustthe heating and flow characteristics of the supplied heated water.

Optionally, the control means comprise a user-interface to selectivelyinitiate the water supply mode. Hence, water may be circulated to thebrewing chamber automatically or upon a user-request via theuser-interface.

The control means may be configured to initiate a brewing mode when themeasured parameter matches the referential curve (including a possibletolerance) corresponding to the “capsule closure mode”.

The control means can be configured to initiate a rinsing and/orde-scaling mode when the measured parameter matches the referentialcurve corresponding to the “empty closure mode”. In particular, thecontrol means can be configured so that said supplied water is heated ata temperature, such as in the range of 55 to 85° C., lower than thenormal brewing temperature, such as in the range of 85 to 98° C.

At least one measured parameter may represent the current consumption ofthe motor.

The control means can be free of end position sensors in the openposition and/or in the closed position. In this case, the measure of thepower consumption by the motor may be used to determine the openposition and/or closed position. The measure of the power consumptionmay be correlated with a time evolution to link the consumption to atime-based expected position of the movable assembly, for instance todistinguish the power consumption resulting from reaching an endposition from the power consumption resulting from interference with anintermediate undesired obstacle.

Alternatively, the control means may include at least one end positionsensor, e.g. two end position sensors in particular for detecting theopen position and/or the closed position.

The motorized beverage machine may include an ingredient capsule betweenthe first and second assemblies, the motor being controlled by thecontrol means to move the assemblies from the open position to theclosed position to form the brewing chamber to contain the ingredientcapsule, the measuring means of the control means being arranged tomeasure at least one parameter representative of the power consumptionof the motor during motion of the assemblies to the closed position withthe capsule between the closing assemblies, the comparing means of thecontrol means being arranged to compare the evolution of said measuredparameter to the set reference, the input means of the control meansbeing arranged to provide to at least one of said activation means theinput resulting from said comparison.

The control means can be configured to detect any abnormal variation incomparison to a referential curve representing the normal evolution ofthe electrical parameter as a function of time and to:

-   -   initiate a water supply mode when no abnormal variation of the        measured parameter relative to the set reference has been        detected and the assembly is in a closed position; and/or    -   provide a safety input to the motor when an abnormal variation        of the measured parameter relative to the set reference is        detected.

More generally, the machine may comprise an ingredient capsule betweenthe first and second assemblies, the motor being arranged to move theassemblies from the open position to the closed position to form thebrewing chamber to contain the ingredient capsule, the motor beingassociated with a power consumption measuring means for detecting viathe measured power consumption: a presence of such capsule between thefirst and second assemblies during closure; and when the assembliesreach the closed position.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described with reference to the schematicdrawings, wherein:

FIG. 1 is a partly schematic and partly perspective view of a beveragemachine according to the invention;

FIG. 2 shows a partial cross-sectional perspective representation of abrewing unit of the beverage machine of FIG. 1 in open position;

FIG. 3 shows a partial cross-sectional perspective representation of aclosed brewing unit of the beverage machine of FIG. 1 in an “emptyclosure mode”;

FIG. 4 shows a partial cross-sectional perspective representation of aclosed brewing unit of the beverage machine of FIG. 1 in a “capsuleclosure mode”; and

FIG. 5 shows a graphic of referential curves of the current absorptionof the motor as a function of time in a “capsule closure mode” and in an“empty closure mode”.

DETAILED DESCRIPTION OF THE INVENTION

An exemplary motorized beverage machine 1 according to the invention isillustrated in FIG. 1. The machine comprises activation means with amotor (3) and a brewing unit 2 which is connected to electric motor 3which drives transmission means 4 for moving brewing unit 2 from an opento a closed position and/or vice versa. Water supply means 5 are alsoprovided as a part of machine 1. Such means 5 may include a waterreservoir 6, a water pump 7 and a water heater 8. Water circulates in awater circuit 9 which is linked to brewing unit 2. Typically, circuit 9is in fluid connection with brewing unit 2. Control means 10 are alsoprovided in machine 1. Control means 10 include a control unit 11,sensors (not represented) and a user interface 12. Control unit 10includes processor(s), memories and programs enabling to provideappropriate inputs to and receive outputs from the different activationmeans of the machine in particular, the pump, heater and motor.

Control means 10 may be connected, e.g. wired or wireless, to userinterface 12, pump 7, heater 8 and various sensors, such as flow-meters,temperature sensors, pressure sensors, ammeter (e.g. for measuring thecurrent consumption of motor 3) such as a Hall sensor. In particular,control means 11 may control electric power switches and/or current andvoltage regulators associated with motor 3, pump 7 and heater 8.

As shown in FIGS. 2 and 3, brewing unit 2 has a first assembly 13 and asecond assembly 14 which are movable relatively one another.

In the context of the present invention, “assembly” may refer to asingle component assembling different functions, e.g. mechanical guidingfunction, mechanical holding function, mechanical piercing function,flow function, pressure function, etc. . . . , and/or refer to aplurality of components assembling the desired functions.

For instance, first assembly 13 is a rear injection assembly 13 andincludes a capsule cage with injection blades 15. Front assembly 14forms a beverage delivery assembly and includes a capsule delivery plate16. Front assembly 14 is associated to an outer casing 17 and is movabletherewith relatively to rear injection assembly 13 which remains fixedto a frame 18 of machine 1. Front delivery assembly 14 includes abeverage outlet 19.

Front delivery assembly 14 is moved relatively to rear injectionassembly 13 by means of motor 3 which drives transmission means 4.

In accordance with the invention, motor 3 is a low power motorconfigured to: generate a maximum torque of no more than 50 mNm; and/orconsume a maximum power of no more than 50 watt, for driving movableassembly 14 between the open and closed positions.

For instance, motor 3 is arranged to generate a maximum torque of atleast 20 mNm, in particular a maximum torque in the range of 25 to 40mNm. Motor 3 can be arranged to consume a maximum power in the range of7 to 25 watt, in particular 10 to 15 watt. The motor can have an angularspeed of up to 10K RPM, such as from 0 to 5000 RPM.

In the open position (FIG. 2), a passage 31 is provided between thefirst and second assemblies 13,14 for allowing the insertion of acapsule 30. The capsule may be positioned in an intermediate position,for example as described in EP 1 646 305 or WO 2009/043630.

In the closed position (FIG. 3), a brewing chamber 29 is formed. Brewingchamber 29 is occupied at least partially by a capsule 30 in a normallyclosed position of the brewing unit (FIG. 4). The capsule may be of anytype and should simply be compatible with brewing chamber 29 and passage31 for being handled by the assemblies during closure and opening of thebrewing unit. Suitable capsules and brewing chambers are for instancedisclosed in EP 0 512 468, EP 0 512 470 and EP 2 068 684.

Transmission means 4 may include various mechanical systems.Transmission means 4 may have a force transmission ratio from the motorto the assembly of at least 1:50, in particular from 1:100 to 1:300 to1:500.

In the embodiment illustrated in FIGS. 1 to 4, transmission means 4includes a gear assembly 20 linked to a cam 22 and cam-follower 23. Fora balanced transmission of the forces on casing 17, cam 22 comprise apair of elongated grooves located on each side of casing 17. Gearassembly 20 comprises a worm drive 21 connected to the motor axle (i.e.to the rotor of motor 3). Worm drive 21 operates a large gear 24, e.g. aspur gear or helical gear, which is fixed to an axle 25 on which sit twolateral smaller gears 26, 27, e.g. spur gears or helical gears orfriction gears. The smaller gears 26, 27 drives a pair of gear segments28, e.g. spur gears or helical gears or friction gears, which movescam-follower 23 and, by way of consequence, move cam 22 with the casing17 from the opened to the closed position and vice versa. In the closedposition gear segments 28 with cam-followers 23 are positioned such thatthe brewing pressure is absorbed across the gear segments without itbeing transmitted to the rest of the drive system, e.g. radially acrossthe gear segments. However, as explained hereafter, the brewing pressurecan be absorbed by the drive system by a suitable configuration.

The gear ratio between worm drive 21 and large gear 24 may be in therange of 1:25 to 1:100, such as 1:50 to 1:80. The gear ratio betweensmall gear 27 and gear segment 28 can be in the range of 1:3 to 1:10, inparticular in the range of 1:5 to 1:8.

For instance, the use of a worm drive 21 in transmission 4 can make thistransmission unidirectional. In other words, force and movement can onlybe transmitted from motor 3 to transmission 4 and not vice versa, wormdrive 21 acting as a stop in the opposite direction. Hence, no furtherstop means is needed to maintain the assemblies in a given position. Itis sufficient to interrupt the powering of motor 3 to secure assemblies13,14 in a given position, in particular in the closed or open position.

In a possible solution, both open and closed end positions aregeometrically made as “hard stops” with no end switches or sensors.

The input for the motor control may involve the user-interface, thecurrent absorption of the motor and a timer of the control unit.

As illustrated in FIG. 5, two different typical curves 40,41 can bedetected over time, e.g. by measuring the power consumption of motor 3,for example by measuring the current consumption of motor 3, inparticular when motor 3 is a DC motor, e.g. operated at generallyconstant voltage.

Curve 40 represents the evolution over time of the current consumptionof motor 3 in the “capsule closure mode”. The closed state of brewingunit 2 in the capsule closure mode is represented in FIG. 4 with acapsule 30 enclosed in the closed brewing chamber.

Curve 41 represents the evolution of the current consumption of motor 3in the “empty closure mode”. The closed state of brewing unit 2 in theempty closure mode is represented in FIG. 3.

Hence, curves 40,41 correspond to a closure movement of assemblies 13,14of brewing unit 2. Likewise, curves can be determined for the openingmovements, e.g. with and without capsule 30 inbetween assemblies 13,14.Such opening curves can be used as a reference set to detect possibledisturbances of an opening movement of assemblies 13,14, e.g. jamming ofa human body part such as a finger between a housing of the machine anda therein movable assembly of brewing unit 2.

Control unit 10 of machine 1 is configured for comparing the variationof the actual current consumption to referential curves 40 and 41depending on the relevant mode the brewing unit is engaged in. Suchconfiguration is obtained by software.

If a capsule 30 is inserted in brewing unit 2, and no abnormal variationof the current absorption is detected in comparison to curve 40, e.g. novariation exceeding 20% of the typical current consumption curve 40, abrewing cycle can be initiated. The start of brewing cycle can betriggered by a command or request on the user's interface 12.Alternatively, the start of the brewing cycle can be triggeredautomatically by the reaching of the closed position.

If no capsule is inserted into brewing chamber 2 and no abnormalvariation of the variation of the current absorption is detected incomparison to curve 41, a rinsing and/or de-scaling mode with reducedtemperature to allow optimal de-scaling and/or save energy is initiatedin the closed position (FIG. 3). The start of rinsing and/or de-scalingcycle can also be triggered by a command or request on the user'sinterface 12. Alternatively, the start of the rinsing and/or de-scalingcycle can be triggered automatically by the reaching of the closedposition. If no capsule is inserted into brewing chamber 2 and noabnormal variation of the variation of the current absorption isdetected in comparison to curve 41, a cup-preheating mode may beinitiated that involves the dispensing of heated water into a user-cupfor preheating thereof prior to preparing and dispensing a beverage.Preheating of the cup may be carried out at beverage preparationtemperature or at a reduced temperature.

More specifically, curve 40 illustrating an exemplary evolution ofcurrent consumption over time by motor 3 when a capsule 30 is insertedinto brewing unit 2, includes various phases:

An initial portion 401, i.e. a sharp increase of current consumptionreflects the start of motion of the movable assembly, in particular thepower consumption needed to overcome the static friction forces. Asecond portion 402, starts at a level slightly below the top of portion401 (the dynamic friction forces being lower than the static frictionforces) and increases slowly. This portion illustrates the increasingresistance caused by a capsule 30 progressively entering brewing chamber29 during closure. A maximum 403 is reached when capsule 30 is forcedout of an intermediate position in which it is supported by stopmembers, e.g. as explained in EP 2 103 236. Thereafter, the currentconsumption drops slightly until it reaches a minimum 404. The currentconsumption 405,406,407 increases due to the deformation and progressivepiercing of capsule 30 by blades 15 during closure. The more or lessflat portion 408 represents the final approach of the assemblies. Thecurrent increase 409 reflects the power needed to stress a biasingspring (not shown) for a play take-up between the assemblies in theclosed position. Once the current consumption reaches maximum 410, themaximum power is consumed by motor 3 which indicates that the motor 3 isblocked: the assemblies are in their closed position.

Curve 41 illustrating an exemplary evolution of current consumption overtime by motor 3 when no capsule is inserted into brewing unit 2,includes various phases:

Portion 411 corresponds to portion 401, i.e. the movable assembly is putin motion. Once the assembly is motion, portions 412,413 and 414illustrate essentially the force distribution of the rotatingcam-follower 23 moving in the straight grooves 22 and assembly 13 movinggenerally perpendicularly to the direction of grooves 22. Portion416,417 illustrate the power consumption increase due to stressing thebiasing spring. Like above, once the current consumption reaches maximum417, the maximum power is consumed by motor 3 which indicates that theresistance against motor 3 is complete: the assemblies are in theirclosed position.

As illustrated in FIG. 5 by way of Example, the time needed for closingthe assemblies when no capsule is inserted into brewing unit 2, isslightly shorter, approx 0.5 sec, than when motor 3 has to overcomeadditional forces caused by the presence of a capsule 3. Overall,closure can be achieved within 2 or 2.5 sec, as illustrated with thisparticular embodiment of the invention.

The time needed for opening of closing the assemblies of a brewing unitmay typically be in the range of 1 to 10 seconds.

When the measure of the current absorption does not match the two abovementioned curves 40, 41, in particular, when the current consumptionsignificantly exceeds the curve before reaching the closed position, itcan be expected that an undesirable obstacle is located between theassemblies or that the system is jammed or suffers from anothermalfunction. Consequently, a safety input can be activated. The safetyinput preferably comprises the operation of inverting the motor actionto move the movable assembly back into the open position. Alternatively,the safety input may amount to reducing or stopping the drive action ofthe motor. This safety measure protects for example the user fromjamming a finger in the running mechanism. For example, the safety inputmay be triggered when the resistance against closure of the assembliesexceeds 50, 80, 100, 125 or 150 N before reaching the closed positionbefore reaching the closed position. For instance, the safety input maybe triggered when an excessive resistance occurs at a distance betweenthe assemblies before closure which is greater than 1 or 2 mm, inparticular greater than 3 mm or 4 mm.

The gear assembly is preferably configured to provide a gear ratio of atleast 1:100, preferably comprised between 1:200 and 1:500 such asbetween 1:250 and 1:450, e.g. 1:300. Due to this relatively high gearratio, another benefit of the present invention comes from thepossibility to use relatively low power motor, for example comprisedbetween 20-50 mNm.

The invention claimed is:
 1. A motorized beverage machine comprising: anactivation member that comprises a motor; a brewing unit that comprisesa first assembly and a second assembly that cooperate together, eachassembly defining a part of a brewing chamber that is configured tocontain an ingredient capsule; at least one of the first and secondassemblies is a movable assembly being (i) movable away from thecooperating assembly into an open position within the machine to formbetween the first and second assemblies a passage through which aningredient capsule passes during an action selected from the groupconsisting of insertion of the ingredient capsule into the brewing unit,removal of the ingredient capsule from the brewing unit, andcombinations thereof, and (ii) movable to the cooperating assembly intoa closed position to form the brewing chamber; and the motor is a lowpower motor configured to perform a motor action selected from the groupconsisting of generating a maximum torque between 20 and 50 mNm,consuming a maximum power of no more than 50 W, and combinationsthereof, to drive the movable assembly between the open and closedpositions; wherein the activation member comprises a transmissionconfigured for transmitting a drive action from the motor to the movableassembly; the transmission comprising a gear assembly, and the gearassembly has a gear ratio of at least 1:100; and the machine comprises acontroller configured to monitor power consumption of the motor todetermine if the movable assembly has reached an obstacle at an endposition, whereby the controller is configured to stop the motor withoutforcing the movable assembly beyond the end position, wherein themachine is free of end position sensors.
 2. The machine of claim 1,wherein the maximum torque of the motor is between 25 and 40 mNm.
 3. Themachine of claim 1, wherein the maximum power of the motor is 7 to 25 W.4. The machine of claim 1, wherein the gear ratio of the gear assemblyis between 1:200 and 1:500.
 5. The machine of claim 1, wherein the gearratio of the gear assembly is 1:300.
 6. The machine of claim 1, whereinthe transmission has a force transmission ratio from the motor to thegear assembly of at least 1:50.
 7. The machine of claim 1, wherein thegear assembly comprises a worm drive.
 8. The machine of claim 1, whereinthe transmission is unidirectional.
 9. The machine of claim 1, whereinthe activation member further comprises: a water supply that isconfigured to supply heated water to the brewing chamber; and thecontroller that is programmed to control the drive action of the motor.10. The machine of claim 9, wherein the controller is configured tomeasure at least one electrical parameter representative of aconsumption of power by the motor; compare to a set reference anevolution of the measured parameter as a function of time during thetransfer of the movable assembly from the open position to the closedposition; and provide to the activation member an input resulting fromcomparing the evolution of the measured parameter to the set reference.11. The machine of claim 10, wherein a safety input is provided by thecontroller to the motor when detecting a variation of the measuredparameter relative to the set reference which is abnormal, the variationbeing deemed abnormal when the measured parameter is selected from thegroup consisting of exceeds a level that is at least 20% above the setreference; corresponds to a resistance to closure caused by the presenceof an obstacle, in between the first and second assemblies movingtowards the closed position and prior to reaching thereof; andcombinations thereof.
 12. The machine of claim 11, wherein the safetyinput comprises inverting the motor action to move the movable assemblyinto the open position or reducing or stopping the motor action.
 13. Themachine of claim 12, wherein the controller detects the abnormalvariation in comparison to a referential curve representing the normalevolution of the electrical parameter as a function of timecorresponding to a mode selected from the group consisting of a mode inwhich the movable assembly is moved into the closed position with aningredient capsule inserted in the brewing chamber; a mode in which themovable assembly is moved into the closed position with no capsuleinserted in the brewing chamber; and combinations thereof.
 14. Themachine of claim 1, comprising an ingredient capsule between the firstand second assemblies, the motor being arranged to move the first andsecond assemblies from the open position to the closed position to formthe brewing chamber to contain the ingredient capsule, the motor beingassociated with a power consumption measuring member configured fordetecting via a measured power consumption a presence of the ingredientcapsule between the first and second assemblies during closure and whenthe first and second assemblies reach the closed position.
 15. Amotorized beverage machine comprising: an activation member thatcomprises a motor; a brewing unit that comprises a first assembly and asecond assembly, the first and second assemblies defining a brewingchamber for containing an ingredient capsule; at least one of the firstand second assemblies being movable away from the other assembly into anopen position and movable to the other assembly into a closed position;the motor is a low power motor designed to generate a maximum torquebetween 20 and 50 mNm and/or consume a maximum power of no more than 50W, for driving the movable assembly between the open and closedpositions; the activation member comprises a transmission memberconfigured for transmitting a drive action from the motor to the movableassembly; and the transmission member comprising a gear assembly, andthe gear assembly has a gear ratio of at least 1:100; and the machinecomprises a controller configured to monitor power consumption of themotor to determine if the movable assembly has reached an obstacle at anend position, whereby the controller is configured to stop the motorwithout forcing the movable assembly beyond the end position, whereinthe machine is free of end position sensors.
 16. The machine of claim 9,wherein the water supply is configured to supply heated water to thebrewing chamber when the movable assembly is in the closed position. 17.The machine of claim 16, wherein the supply of heated water iscontrolled by a temperature sensor, a pressure sensor and/or aflowmeter.
 18. The machine of claim 9, wherein the controller comprisesa user-interface to selectively initiate the water supply.